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Effects of Surfactants on the Toxicitiy of Glyphosate, with Specific Reference to RODEO
SERA TR 97-206-1b Effects of Surfactants on the Toxicitiy of Glyphosate, with Specific Reference to RODEO Submitted to: Leslie Rubin, COTR Animal and Plant Health Inspection Service (APHIS) Biotechnology, Biologics and Environmental Protection Environmental Analysis and Documentation United States Department of Agriculture Suite 5A44, Unit 149 4700 River Road Riverdale, MD 20737 Task No. 5 USDA Contract No. 53-3187-5-12 USDA Order No. 43-3187-7-0028 Prepared by: Gary L. Diamond Syracuse Research Corporation Merrill Lane Syracuse, NY 13210 and Patrick R. Durkin Syracuse Environmental Research Associates, Inc. 5100 Highbridge St., 42C Fayetteville, New York 13066-0950 Telephone: (315) 637-9560 Fax: (315) 637-0445 CompuServe: 71151,64 Internet: [email protected] February 6, 1997 TABLE OF CONTENTS EXECUTIVE SUMMARY ......................................... iii 1. INTRODUCTION .............................................1 2. CONSTITUENTS OF SURFACTANT FORMULATIONS USED WITH RODE0 ....4 2.1. AGRI-DEX ..........................................4 2.2. LI-700 .............................................4 2.3. R-11 ...............................................6 2.4. LATRON AG-98 ......................................6 2.5. LATRON AG-98 AG ....................................7 3. INFORMATION ON EFFECTS OF SURFACTANT FORMULATIONS ON THE TOXICITY OF RODEO ................................8 3.1. HUMAN HEALTH ......................................8 3.1.1. LI 700 ........................................8 3.1.2. Phosphatidylcholine ................................8 -
Sanitization: Concentration, Temperature, and Exposure Time
Sanitization: Concentration, Temperature, and Exposure Time Did you know? According to the CDC, contaminated equipment is one of the top five risk factors that contribute to foodborne illnesses. Food contact surfaces in your establishment must be cleaned and sanitized. This can be done either by heating an object to a high enough temperature to kill harmful micro-organisms or it can be treated with a chemical sanitizing compound. 1. Heat Sanitization: Allowing a food contact surface to be exposed to high heat for a designated period of time will sanitize the surface. An acceptable method of hot water sanitizing is by utilizing the three compartment sink. The final step of the wash, rinse, and sanitizing procedure is immersion of the object in water with a temperature of at least 170°F for no less than 30 seconds. The most common method of hot water sanitizing takes place in the final rinse cycle of dishwashing machines. Water temperature must be at least 180°F, but not greater than 200°F. At temperatures greater than 200°F, water vaporizes into steam before sanitization can occur. It is important to note that the surface temperature of the object being sanitized must be at 160°F for a long enough time to kill the bacteria. 2. Chemical Sanitization: Sanitizing is also achieved through the use of chemical compounds capable of destroying disease causing bacteria. Common sanitizers are chlorine (bleach), iodine, and quaternary ammonium. Chemical sanitizers have found widespread acceptance in the food service industry. These compounds are regulated by the U.S. Environmental Protection Agency and consequently require labeling with the word “Sanitizer.” The labeling should also include what concentration to use, data on minimum effective uses and warnings of possible health hazards. -
Pulmonary Surfactant: the Key to the Evolution of Air Breathing Christopher B
Pulmonary Surfactant: The Key to the Evolution of Air Breathing Christopher B. Daniels and Sandra Orgeig Department of Environmental Biology, University of Adelaide, Adelaide, South Australia 5005, Australia Pulmonary surfactant controls the surface tension at the air-liquid interface within the lung. This sys- tem had a single evolutionary origin that predates the evolution of the vertebrates and lungs. The lipid composition of surfactant has been subjected to evolutionary selection pressures, partic- ularly temperature, throughout the evolution of the vertebrates. ungs have evolved independently on several occasions pendent units, do not necessarily stretch upon inflation but Lover the past 300 million years in association with the radi- unpleat or unfold in a complex manner. Moreover, the many ation and diversification of the vertebrates, such that all major fluid-filled corners and crevices in the alveoli open and close vertebrate groups have members with lungs. However, lungs as the lung inflates and deflates. differ considerably in structure, embryological origin, and Surfactant in nonmammals exhibits an antiadhesive func- function between vertebrate groups. The bronchoalveolar lung tion, lining the interface between apposed epithelial surfaces of mammals is a branching “tree” of tubes leading to millions within regions of a collapsed lung. As the two apposing sur- of tiny respiratory exchange units, termed alveoli. In humans faces peel apart, the lipids rise to the surface of the hypophase there are ~25 branches and 300 million alveoli. This structure fluid at the expanding gas-liquid interface and lower the sur- allows for the generation of an enormous respiratory surface face tension of this fluid, thereby decreasing the work required area (up to 70 m2 in adult humans). -
Micelle Formation and the Hydrophobic Effect†
6778 J. Phys. Chem. B 2004, 108, 6778-6781 Micelle Formation and the Hydrophobic Effect† Lutz Maibaum,‡ Aaron R. Dinner,§ and David Chandler*,‡ Department of Chemistry, UniVersity of California, Berkeley, California 94720, and Department of Chemistry, UniVersity of Chicago, Chicago, Illinois 60637 ReceiVed: NoVember 14, 2003; In Final Form: January 14, 2004 The tendency of amphiphilic molecules to form micelles in aqueous solution is a consequence of the hydrophobic effect. The fundamental difference between micelle assembly and macroscopic phase separation is the stoichiometric constraint that frustrates the demixing of polar and hydrophobic groups. We present a theory for micelle assembly that combines the account of this constraint with a description of the hydrophobic driving force. The latter arises from the length scale dependence of aqueous solvation. The theoretical predictions for temperature dependence and surfactant chain length dependence of critical micelle concentrations for nonionic surfactants agree favorably with experiment. I. Introduction in accord with experimental observations. An appendix is used to augment the discussion in section II. This paper concerns the formation of micelles, which are the simplest form of amphiphilic assemblies. Our treatment of this II. Theory phenomenon is based upon the length scale dependence of hydrophobic effects.1,2 Namely, the free energy to solvate small A. Law of Mass Action. We consider an aqueous solution hydrophobic molecules scales linearly with solute volume, of neutral amphiphilic molecules (i.e., nonionic surfactants), each whereas that to solvate large hydrophobic species scales linearly of which has a single alkyl chain as its hydrophobic tail. In with surface area. The crossover from one regime to the other general, amphiphiles can form aggregates of various sizes and occurs when the oily species presents a surface in water shapes. -
Tutorial on Working with Micelles and Other Model Membranes
Tutorial on Working with Micelles and Model Membranes Chuck Sanders Dept. of Biochemistry, Dept. of Medicine, and Center for Structural Biology Vanderbilt University School of Medicine. http://structbio.vanderbilt.edu/sanders/ March, 2017 There are two general classes of membrane proteins. This presentation is on working with integral MPs, which traditionally could be removed from the membrane only by dissolving the membrane with detergents or organic solvents. Multilamellar Vesicles: onion-like assemblies. Each layer is one bilayer. A thin layer of water separates each bilayer. MLVs are what form when lipid powders are dispersed in water. They form spontaneously. Cryo-EM Micrograph of a Multilamellar Vesicle (K. Mittendorf, C. Sanders, and M. Ohi) Unilamellar Multilamellar Vesicle Vesicle Advances in Anesthesia 32(1):133-147 · 2014 Energy from sonication, physical manipulation (such as extrusion by forcing MLV dispersions through filters with fixed pore sizes), or some other high energy mechanism is required to convert multilayered bilayer assemblies into unilamellar vesicles. If the MLVs contain a membrane protein then you should worry about whether the protein will survive these procedures in folded and functional form. Vesicles can also be prepared by dissolving lipids using detergents and then removing the detergent using BioBeads-SM dialysis, size exclusion chromatography or by diluting the solution to below the detergent’s critical micelle concentration. These are much gentler methods that a membrane protein may well survive with intact structure and function. From: Avanti Polar Lipids Catalog Bilayers can undergo phase transitions at a critical temperature, Tm. Native bilayers are usually in the fluid (liquid crystalline) phase. -
Henry's Law Constants and Micellar Partitioning of Volatile Organic
38 J. Chem. Eng. Data 2000, 45, 38-47 Henry’s Law Constants and Micellar Partitioning of Volatile Organic Compounds in Surfactant Solutions Leland M. Vane* and Eugene L. Giroux United States Environmental Protection Agency, National Risk Management Research Laboratory, 26 West Martin Luther King Drive, Cincinnati, Ohio 45268 Partitioning of volatile organic compounds (VOCs) into surfactant micelles affects the apparent vapor- liquid equilibrium of VOCs in surfactant solutions. This partitioning will complicate removal of VOCs from surfactant solutions by standard separation processes. Headspace experiments were performed to quantify the effect of four anionic surfactants and one nonionic surfactant on the Henry’s law constants of 1,1,1-trichloroethane, trichloroethylene, toluene, and tetrachloroethylene at temperatures ranging from 30 to 60 °C. Although the Henry’s law constant increased markedly with temperature for all solutions, the amount of VOC in micelles relative to that in the extramicellar region was comparatively insensitive to temperature. The effect of adding sodium chloride and isopropyl alcohol as cosolutes also was evaluated. Significant partitioning of VOCs into micelles was observed, with the micellar partitioning coefficient (tendency to partition from water into micelle) increasing according to the following series: trichloroethane < trichloroethylene < toluene < tetrachloroethylene. The addition of surfactant was capable of reversing the normal sequence observed in Henry’s law constants for these four VOCs. Introduction have long taken advantage of the high Hc values for these compounds. In the engineering field, the most common Vast quantities of organic solvents have been disposed method of dealing with chlorinated solvents dissolved in of in a manner which impacts human health and the groundwater is “pump & treat”swithdrawal of ground- environment. -
Dive Theory Guide
DIVE THEORY STUDY GUIDE by Rod Abbotson CD69259 © 2010 Dive Aqaba Guidelines for studying: Study each area in order as the theory from one subject is used to build upon the theory in the next subject. When you have completed a subject, take tests and exams in that subject to make sure you understand everything before moving on. If you try to jump around or don’t completely understand something; this can lead to gaps in your knowledge. You need to apply the knowledge in earlier sections to understand the concepts in later sections... If you study this way you will retain all of the information and you will have no problems with any PADI dive theory exams you may take in the future. Before completing the section on decompression theory and the RDP make sure you are thoroughly familiar with the RDP, both Wheel and table versions. Use the appropriate instructions for use guides which come with the product. Contents Section One PHYSICS ………………………………………………page 2 Section Two PHYSIOLOGY………………………………………….page 11 Section Three DECOMPRESSION THEORY & THE RDP….……..page 21 Section Four EQUIPMENT……………………………………………page 27 Section Five SKILLS & ENVIRONMENT…………………………...page 36 PHYSICS SECTION ONE Light: The speed of light changes as it passes through different things such as air, glass and water. This affects the way we see things underwater with a diving mask. As the light passes through the glass of the mask and the air space, the difference in speed causes the light rays to bend; this is called refraction. To the diver wearing a normal diving mask objects appear to be larger and closer than they actually are. -
Biomechanics of Safe Ascents Workshop
PROCEEDINGS OF BIOMECHANICS OF SAFE ASCENTS WORKSHOP — 10 ft E 30 ft TIME AMERICAN ACADEMY OF UNDERWATER SCIENCES September 25 - 27, 1989 Woods Hole, Massachusetts Proceedings of the AAUS Biomechanics of Safe Ascents Workshop Michael A. Lang and Glen H. Egstrom, (Editors) Copyright © 1990 by AMERICAN ACADEMY OF UNDERWATER SCIENCES 947 Newhall Street Costa Mesa, CA 92627 All Rights Reserved No part of this book may be reproduced in any form by photostat, microfilm, or any other means, without written permission from the publishers Copies of these Proceedings can be purchased from AAUS at the above address This workshop was sponsored in part by the National Oceanic and Atmospheric Administration (NOAA), Department of Commerce, under grant number 40AANR902932, through the Office of Undersea Research, and in part by the Diving Equipment Manufacturers Association (DEMA), and in part by the American Academy of Underwater Sciences (AAUS). The U.S. Government is authorized to produce and distribute reprints for governmental purposes notwithstanding the copyright notation that appears above. Opinions presented at the Workshop and in the Proceedings are those of the contributors, and do not necessarily reflect those of the American Academy of Underwater Sciences PROCEEDINGS OF THE AMERICAN ACADEMY OF UNDERWATER SCIENCES BIOMECHANICS OF SAFE ASCENTS WORKSHOP WHOI/MBL Woods Hole, Massachusetts September 25 - 27, 1989 MICHAEL A. LANG GLEN H. EGSTROM Editors American Academy of Underwater Sciences 947 Newhall Street, Costa Mesa, California 92627 U.S.A. An American Academy of Underwater Sciences Diving Safety Publication AAUSDSP-BSA-01-90 CONTENTS Preface i About AAUS ii Executive Summary iii Acknowledgments v Session 1: Introductory Session Welcoming address - Michael A. -
Lecture 3. the Basic Properties of the Natural Atmosphere 1. Composition
Lecture 3. The basic properties of the natural atmosphere Objectives: 1. Composition of air. 2. Pressure. 3. Temperature. 4. Density. 5. Concentration. Mole. Mixing ratio. 6. Gas laws. 7. Dry air and moist air. Readings: Turco: p.11-27, 38-43, 366-367, 490-492; Brimblecombe: p. 1-5 1. Composition of air. The word atmosphere derives from the Greek atmo (vapor) and spherios (sphere). The Earth’s atmosphere is a mixture of gases that we call air. Air usually contains a number of small particles (atmospheric aerosols), clouds of condensed water, and ice cloud. NOTE : The atmosphere is a thin veil of gases; if our planet were the size of an apple, its atmosphere would be thick as the apple peel. Some 80% of the mass of the atmosphere is within 10 km of the surface of the Earth, which has a diameter of about 12,742 km. The Earth’s atmosphere as a mixture of gases is characterized by pressure, temperature, and density which vary with altitude (will be discussed in Lecture 4). The atmosphere below about 100 km is called Homosphere. This part of the atmosphere consists of uniform mixtures of gases as illustrated in Table 3.1. 1 Table 3.1. The composition of air. Gases Fraction of air Constant gases Nitrogen, N2 78.08% Oxygen, O2 20.95% Argon, Ar 0.93% Neon, Ne 0.0018% Helium, He 0.0005% Krypton, Kr 0.00011% Xenon, Xe 0.000009% Variable gases Water vapor, H2O 4.0% (maximum, in the tropics) 0.00001% (minimum, at the South Pole) Carbon dioxide, CO2 0.0365% (increasing ~0.4% per year) Methane, CH4 ~0.00018% (increases due to agriculture) Hydrogen, H2 ~0.00006% Nitrous oxide, N2O ~0.00003% Carbon monoxide, CO ~0.000009% Ozone, O3 ~0.000001% - 0.0004% Fluorocarbon 12, CF2Cl2 ~0.00000005% Other gases 1% Oxygen 21% Nitrogen 78% 2 • Some gases in Table 3.1 are called constant gases because the ratio of the number of molecules for each gas and the total number of molecules of air do not change substantially from time to time or place to place. -
Carbon Monoxide Levels and Risks
Carbon Monoxide Levels and Risks CO Level Action CO Level Action 0.1 ppm Natural atmosphere level or clean air. 70-75 ppm Heart patients experience an increase in chest pain. Significant decrease in 1 ppm An increase of 1 ppm in the maximum dai- oxygen available to the myocardium/ ly one-hour exposure is associated with a heart (HbCO 10%). 0.96 percent increase in the risk of hospi- 100 ppm Headache, tiredness, dizziness, nausea talization from cardiovascular disease within 2 hrs of exposure. At 5 hrs, dam- among people over the age of 65. age to hearts and brains. (Lewey & Drabkin) (Circulation: Journal of the AHA, Sept, 2009) 200 ppm Healthy adults will have headache, nau- 3-7 ppm 6% increase in the rate of admission in sea at this level. hospitals of non-elderly for asthma. (L. Shep- pard et al.,Epidemiology, Jan 1999) NIOSH & OSHA recommend evacua- tion of the workplace at this level. 5-6 ppm Significant risk of low birth weight if exposed during last trimester - in a study 400 ppm Frontal headache within 1-2 hours—life of 125,573 pregnancies (Ritz & Yu, Environ. threatening within 3 hours. Health Perspectives, 1999). 500 ppm Concentration in a garage when a cold 9 ppm EPA and WHO maximum outdoor air lev- car is started in an open garage and el, all ages, (TWA, 8 hrs). Maximum allow- warmed up for 2 minutes. (Greiner, 1997) able indoor level (ASHRAE) 800 ppm Healthy adults will have nausea, dizzi- Lowest CO level producing significant ef- ness and convulsions within 45 fects on cardiac function (ST-segment minutes. -
The Mechanism Whereby Bile Acid Micelles Increase the Rate of Fatty Acid and Cholesterol Uptake Into the Intestinal Mucosal Cell
The mechanism whereby bile acid micelles increase the rate of fatty acid and cholesterol uptake into the intestinal mucosal cell. H Westergaard, J M Dietschy J Clin Invest. 1976;58(1):97-108. https://doi.org/10.1172/JCI108465. Research Article Studies were undertaken to define the mechanism whereby bile acid facilitates fatty acid and cholesterol uptake into the intestinal mucosal cell. Initial studies showed that the rate of uptake (Jd) of several fatty acids and cholesterol was a linear function of the concentration of these molecules in the bulk phase if the concentration of bile acid was kept constant. In contrast, Jd decreased markedly when the concentration of bile acid was increased relative to that of the probe molecule but remained essentially constant when the concentration of both the bile acid and probe molecule was increased in parallel. In other studies Jd for lauric acid measured from solutions containing either 0 or 20 mM taurodeoxycholate and saturated with the fatty acid equaled 79.8+/-5.2 and 120.8+/-9.4 nmol.min(-1).100 mg(-1), respectively: after correction for unstirred layer resistance, however, the former value equaled 113.5+/-7.1 nmol.min(- 1).100 mg(-1). Maximum values of Jd for the saturated fatty acids with 12, 16, and 18 carbons equaled 120.8+/-9.4, 24.1+/-3.2, and 13.6+/-1.1 nmol.min(-1).100 mg(-1), respectively. These values essentially equaled those derived by multiplying the maximum solubility times the passive permeability coefficients appropriate for each of these compounds. The theoretical equations were then derived that define the expected behavior of Jd for the various lipids under these different experimental circumstances where the mechanism of absorption was assumed to occur either by […] Find the latest version: https://jci.me/108465/pdf The Mechanism Whereby Bile Acid Micelles Increase the Rate of Fatty Acid and Cholesterol Uptake into the Intestinal Mucosal Cell HEmN WESTEGAABD and JoHN M. -
Rheology of Surfactants: Wormlike Micelles and Lamellar Liquid Crystalline Phase - O
RHEOLOGY - Vol. II - Rheology of Surfactants: Wormlike Micelles and Lamellar Liquid Crystalline Phase - O. Manero, F. Bautista, J. E. Puig RHEOLOGY OF SURFACTANTS: WORMLIKE MICELLES AND LAMELLAR LIQUID CRYSTALLINE PHASES O. Manero Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, A.P. 70-360, México, D.F., 04510 F. Bautista Departamento de Física, Universidad de Guadalajara, Guadalajara, Jal., 44430, México J. E. Puig Departamento de Ingeniería Química, Universidad de Guadalajara, Guadalajara, Jal., 44430, México Keywords: Surfactants. Rheology, Linear viscoelasticity, Nonlinear viscoelasticity, Wormlike micelles, Lamellar liquid crystalline phases, Shear banding, Shear thickening, Stability, Heterogeneous flows, Flow-concentration coupling. Contents 1. Introduction 2. Wormlike Micellar Systems 2.1. Linear Viscoelasticity 2.2. Non-linear Viscoelasticiy 2.2.1. Shear banding Flow 2.2.2. Transient flows 2.2.3. Stability 2.3. Shear banding and linear viscoelasticity 2.4. Flow concentration coupling 2.5. Shear thickening 3. Surfactant Lamellar Liquid Crystal Phases 4. Concluding Remarks Acknowledgements Glossary UNESCO – EOLSS Bibliography Biographical Sketches Summary SAMPLE CHAPTERS In this chapter, the rheology of a special class of complex fluids is analyzed and reviewed. In particular, attention is focused on the dynamic behavior of systems constituted by aqueous phases of surfactants, namely, micellar solutions and lamellar liquid crystalline phases. Surfactants are molecules that possess a polar head and a non- polar tail (i.e., amphiphiles). The polar head may be nonionic or it may posses a charge, in which case they are classified as anionic (negatively charged), cationic (positively charged) and zwitterionic or amphoteric. In ionic surfactants, the polar head is balanced ©Encyclopedia of Life Support Systems (EOLSS) RHEOLOGY - Vol.